This time, it's puberty.
Or really, pre-puberty, since he's 7 1/2. But the testosterone has been kicking in gradually since around 3 years old, spiked a lot at 6 (playing doctor), eased off mid-to-late 6, and then started ramping up around 7 again. Plus or minus - for kids with a constitutional growth delay it will be a few years later (about 10% of the population has this normal variation in growth pattern - the curve is lower but continues longer into adulthood - guys for example can still be gaining height into their 20's, and may not hit puberty until several years after the average).
When we rearranged the bedrooms, the boys got the top bunks. (When I say bedrooms, I mean all two of them. Yes, for six people. Tiny house.) To give them some privacy, we set up curtains on cable around their bunks.
Mostly, Mr B has not slept in his bunk. He'd rather sleep next to mom or dad on the trundle on the floor, or in our bed. It's a regular cycle of cosleepers - and mainly, we don't mind too much. Sleep is good. And they'll already know how to not steal the covers from their partner/spouse/whomever when they grow up. Providing a long-term view, there...
But all of a sudden, not only is Mr B needing to wrestle with everyone, he's vanishing behind the curtain for long spans of time. With The Book. (It's So Amazing!: A Book about Eggs, Sperm, Birth, Babies, and Families (The Family Library))
I'd read somewhere a long time ago (when I was researching growth issues due to Mr B's crash in growth) that testosterone tends to come in short intense bursts, in different patterns (I'm not sure they know why it happens in the patterns it happens in). Three days of 'testosterone poisoning' at a go, with (at least in the early days) some 'down time' between them. (I use the poisoning term with both genders, so it isn't an attack on guy hormones... I think of my peri-menopausal hyper-ovulatory stages as estrogen or progesterone poisoning, too.)
In our experience, the three day thing seems about right. Mr G definitely does three day cycles. We can see it starting, because he is suddenly VERY PHYSICAL. Wrestling, cuddling, pushing on his sibs or friends, leaning against me, sitting too close, kicking the table when he sits at it, fidget, climb, leap, etc. My sister said (if I recall correctly) that a friend of hers had described it for her (she is the single parent of an only son and wanted some insight) - and it felt to him like a need to touch everyone and everything all the time. Huge sensory impulse and drive. I don't know that it shows up like that for everyone, but it sure looks like it from the outside. I'm borrowing her explanation to her son, because it makes sense - she said that you'll start wanting to touch everyone, and one of the jobs of puberty is learning how to Not Do That. It also means finding outlets for the urge to be physical, because I know it is a bad idea to try to fight biology entirely. Channel it is more effective, because if we put a lid on it, it will just leak out sideways somewhere else. And that's usually even less useful.
So, we now go into cycle two of this pattern, at different levels. Mr B is just starting out, and Mr G is well into the early stage of official puberty. Like, his mustache is starting to darken, and the rest of his body is tracking along on development just fine. Unfortunately that also means he already has acne at 11 years old (though the essential oil skin care approach I use for me, which works astonishingly well when NOTHING ever worked including tetracycline, also works for him. Plus it smells nice...). He's also doing plenty of hinting that he's okay with learning about sex. Only, maybe not from mom. And probably not from dad. And maybe not from school, either (oh the horror of talking puberty with Teachers, and Other Kids, and .... shudder). Books is good. We have this one (What's Going on Down There?: Answers to Questions Boys Find Hard to Ask ), which is fabulous - gives great information, including about sex, without having a moral stance on it one way or another. It is very clear that your family determines the start point for a moral position. They talk about STDs and pregnancy and all that grody (er, interesting) stuff.
But that's a bit over Mr B's level. Even though Mr G started reading the What's Going on Down There book at around 8, I think. Maybe 9. Mr B isn't ready for that yet, and likely won't be until he's older than Mr G was. There are a few books out there for younger boys, but they're also mainly aimed at 8-10 age.
But, we're doing okay with The Book, which has some very nice drawn art, and expresses the squeamishness as well as the curiosity rather effectively. Mr G was never squeamish, but Mr B is very prone to blushes and such - very much an F, feelings and values and 'what does this mean about me that you saw me reading this book'.
If I can't find him, I'm now getting used to looking in the bedroom to see if his curtains are drawn. If they're closed, he's probably in there, reading - or whatever. And if he's closing doors and doing 'stuff' behind them. He's suddenly very entertained by his foreskin (no, you can't do that while watching tv with your family, you can do that in your room by yourself). He's learning to do tricks with his parts (he showed me).
Hey, at least overall, he's not mortified by his parts. So that's a fine thing.
It's a little entertaining from this perspective. In a way, charming in his fascination, and in his silly shyness and embarrassment when he gets caught doing something where he shouldn't (nothing awful, just 'please take it somewhere else, thanks!'). And yes, it tends to run in three-day bouts with him, too. Complete with the sudden need to wrestle with his brother.
Right on schedule.